Question extracted from RD sharma of class 10th, Chapter no. 4
Chapter name:- Triangles
Exercise :- 4.2
This is very basic and important questions. And has been asked in several times in exams.

We have ΔABC,

in which D and E are points on the sides AB and AC respectively such that DE || BC.

Also it is given that AD = 2 cm, AB = 6 cm and AC = 9 cm,

Now we have  to find AE

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RD sharma, DHANPAT RAI publication